The 12 km deep earthquake was earlier mentioned as 4.7-magnitude by GNS Science.

The quake struck earthquake-rattled city of Christchurch at about 8:30 p.m. and there were no initial reports of major damage or injuries.

Christchurch has been hit frequently by tremors for more than one year now, including a shattering quake of 6.1-magnitude that killed 181 people, on February 22 this year, and destroyed most of the city's downtown.